UISearchBar textDidChange data from plist - swift

Question

I'd like to search through items of my plist. The plist consists of an array of dictionaries. Each key/value represents Strings/Ints, etc but that isn't important.
As you'll see in the tableViewController class below, I've currently got an array that I have typed. I know I need to make an array of objects/items from my plist but I can't work out how to reference objects from the plist in the view controller.
View controller.swift file:
import UIKit
class TableViewController: UITableViewController, UISearchResultsUpdating {
var array = ["Example 1", "Example 2", "Example 3"]
var filteredArray = [String]()
var searchController = UISearchController()
var resultsController = UITableViewController()
override func viewDidLoad() {
super.viewDidLoad()
searchController = UISearchController(searchResultsController: resultsController)
tableView.tableHeaderView = searchController.searchBar
searchController.searchResultsUpdater = self
resultsController.tableView.delegate = self
resultsController.tableView.dataSource = self
}
//Added func to update search results
func updateSearchResults(for searchController: UISearchController) {
filteredArray = array.filter({ (array:String) -> Bool in
if array.contains(searchController.searchBar.text!) {
return true
} else {
return false
}
})
resultsController.tableView.reloadData()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
extension TableViewController {
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if tableView == resultsController.tableView {
return filteredArray.count
} else {
return array.count
}
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
if tableView == resultsController.tableView {
cell.textLabel?.text = filteredArray[indexPath.row]
} else {
cell.textLabel?.text = array[indexPath.row]
}
return cell
}
}
I've tried solving this by creating an object class from a tutorial on plists. It uses the example of a periodic table of elements:
import UIKit
struct Element {
enum State: String {
case Solid, Liquid, Gas
}
let atomicNumber: Int
let atomicWeight: Float
let discoveryYear: String
let group: Int
let name: String
let period: Int
let radioactive: Bool
let state: State
let symbol: String
// Position in the table
let horizPos: Int
let vertPos: Int
}
extension Element {
enum ErrorType: Error {
case noPlistFile
case cannotReadFile
}
/// Load all the elements from the plist file
static func loadFromPlist() throws -> [Element] {
// First we need to find the plist
guard let file = Bundle.main.path(forResource: "Element", ofType: "plist") else {
throw ErrorType.noPlistFile
}
// Then we read it as an array of dict
guard let array = NSArray(contentsOfFile: file) as? [[String: AnyObject]] else {
throw ErrorType.cannotReadFile
}
// Initialize the array
var elements: [Element] = []
// For each dictionary
for dict in array {
// We implement the element
let element = Element.from(dict: dict)
// And add it to the array
elements.append(element)
}
// Return all elements
return elements
}
/// Create an element corresponding to the given dict
static func from(dict: [String: AnyObject]) -> Element {
let atomicNumber = dict["atomicNumber"] as! Int
let atomicWeight = Float(dict["atomicWeight"] as! String) ?? 0
let discoveryYear = dict["discoveryYear"] as! String
let group = dict["group"] as! Int
let name = dict["name"] as! String
let period = dict["period"] as! Int
let radioactive = dict["radioactive"] as! String == "True"
let state = State(rawValue: dict["state"] as! String)!
let symbol = dict["symbol"] as! String
let horizPos = dict["horizPos"] as! Int
let vertPos = dict["vertPos"] as! Int
return Element(atomicNumber: atomicNumber,
atomicWeight: atomicWeight,
discoveryYear: discoveryYear,
group: group,
name: name,
period: period,
radioactive: radioactive,
state: state,
symbol: symbol,
horizPos: horizPos,
vertPos: vertPos)
}
}
And in the viewController class, instead of having
var array = ["Example 1", "Example 2", "Example 3"]
I've tried variations of
var array = Element["name"]
and
var array = elements.name
But they obviously don't work because the reference to the plist is in the object class.
If anyone has any idea on how to solve this using swift 3/xcode 8 I would be very appreciative!!

Answer 1

I hope your question is still relevant. As I understand, you can't filter your array, right? If so, I recommend you to take a look at this and this tutorials. Both of them are representing a little bit different approaches to load filtered array, but it doesn't matter much, they work.
P.S. I don't recommend you to make a special tableView for searching, if you want to customize it hereafter, because you will have to do it programmaticly later.
It will be more efficiant to do like this:
If searchController.isActive {
// do some stuff
} else { // another stuff }
But it is just my opinion. I hope my question will help ;).

Answer 2

Thanks for the links Oleg. They were really good!!
It wasn't so much the filtering I had a problem with but actually parsing objects from my plist into a tableview. It took me a few days but I found an answer in case other people were also having the same problem. Keep in mind I'm reasonably new to this and so it might not be the best/perfect way of doing it but it works.
In viewDidLoad, I made a reference to the plist using the following code:
let path = Bundle.main.path(forResource: "Elements", ofType: "plist")
let dictArray = NSArray(contentsOfFile: path!)
I'm not sure of the relevance but I'm pretty sure this next bit is needed if the plist ever needed to be updated. (Also in viewDidLoad)
for elementItem in dictArray! {
let newElement : Element = Element(state:((elementItem as AnyObject).object(forKey: "state")) as! String,
atomicNumber:((elementItem as AnyObject).object(forKey: "atomicNumber")) as! Int,
atomicWeight:((elementItem as AnyObject).object(forKey: "atomicWeight")) as! Float,
discoveryYear:((elementItem as AnyObject).object(forKey: "discoveryYear")) as! String
etc. for each of the keys in the dictionary in the same order as in the Element object in the question. Then (also in viewDidLoad):
elementsArray.append(newElement)
Then its pretty easy, in cellForRow I just have to make a new variable that refers back to the object and I can call up each/any of the associated dictionary keys. E.g.:
let element : Element
cell.textLabel!.text = element.name
cell.detailTextLabel?.text = element.symbol
return cell
Like I said, I know its not perfect but it worked for me. I've heard its not best practice to put too much information in viewDidLoad, so someone else might be able to confirm or provide a better answer.